Interactions between lymphocyte membrane molecules. II. Characterization of an interaction between B lymphocyte surface IgD and Fc IgG receptors that differs from the surface IgM-Fc IgG receptor interaction.
The B lymphocyte surface membrane receptors IgD (sigD) and Fc IgG receptors (Fc gamma R) were evaluated for interactions by means of immunofluorescence. Ligand-(F(ab')2 anti-delta) induced capping of sIgD resulted in co-capping of Fc gamma R if the latter were occupied during the capping process by soluble antigen-antibody complexes (which themselves provided insufficient cross-linking to result in capping), but not if the Fc gamma R were occupied by monomeric IgG or unoccupied. Capping of Fc gamma R by highly cross-linked complexes did not cause co-capping of sIgD occupied by monomeric F(ab') anti-delta. The interaction between sIgD and Fc gamma R was specific in that cross-reactions between ligands were excluded and ligand-induced capping of sIgD did not cause co-capping of ligand-occupied sIgM or I-A antigens. The sIgD-Fc gamma R interaction occurred on only approximately 60% of B lymphocytes, and this B cell subpopulation did not correlate with other B cell subpopulations (CBA/N strain B cells and B cells bearing either large or small amounts of sIgD). The sIgD-Fc gamma R interaction differed from the sIgM-Fc gamma R interaction in that co-redistribution of the Fc gamma R was occupied by monomeric IgG and involved nearly all B lymphocytes. The qualitative and quantitative differences between the sIgD-Fc gamma R and sIgM-Fc gamma R interactions suggest a mechanism whereby the two antigen receptors could provide different signals to the B lymphocyte.
D000818:Animals; D000918:Antibody Specificity; D001402:B-Lymphocytes / Q000145:classification / Q000276:immunology / Q000378:metabolism*; D002462:Cell Membrane / Q000276:immunology / Q000378:metabolism; D007072:Immunoglobulin D / Q000378:metabolism; D007074:Immunoglobulin G / Q000378:metabolism; D007075:Immunoglobulin M / Q000378:metabolism; D007142:Immunoglobulin gamma-Chains / Q000378:metabolism; D008024:Ligands; D008214:Lymphocytes / Q000276:immunology / Q000378:metabolism*; D046911:Macromolecular Substances; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D011817:Rabbits; D011947:Receptors, Antigen, B-Cell / Q000378:metabolism*; D011961:Receptors, Fc / Q000378:metabolism*
D007072:Immunoglobulin D; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007142:Immunoglobulin gamma-Chains; D008024:Ligands; D046911:Macromolecular Substances; D011947:Receptors, Antigen, B-Cell; D011961:Receptors, Fc